Assistant Editor David J. Hoff and Photo Editor Allison Shelley are filing periodic travel dispatches from Antarctica, where they are on assignment covering a National Science Foundation program for teachers. Here they travel to the Dry Valleys, a polar desert where it hasn’t rained for millions of years, and take a “morale cruise” on a Coast Guard ice breaker.
Lake Fryxel, Antarctica (Jan. 12)—In a 30-minute helicopter ride from the McMurdo Research Station, you can go from standing on a vast plane of sea ice to trekking in a valley where it hasn’t rained in millions of years.
The flight takes you directly east across McMurdo Sound, with mountains to your left and the spot where the ice meets the Ross Sea on the right. The helicopter turns to the left into a valley between two banks of mountains. These are the Dry Valleys, a polar desert drier than the Sahara.
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Our first view of Taylor Valley. |
This area is so arid a seal carcass 100 or more years old will remain intact. With no predators to eat them and no moisture to decompose them, the carcasses lie as they did when they died years ago. On some, the whiskers still point away from the animals’ mouths.
The valleys have formed over the past 600 million years. They remain dry because the mountains to their west are too high for the ice sheet to melt into them. A few glaciers feed into the valleys, but not enough to create much moisture. Several small, frozen lakes and a few patches of snow dot the landscape, but it’s composed mostly of fine soil filled with gravelly rocks.
It snows here occasionally, as recently as this week, but rarely more than a few inches a year. The top layer of soil, which ranges from 4 to 12 inches in depth, is a mixture of fine dust, pebbles, and larger rocks. Underneath is permafrost.
Allison Shelley and I flew to Lake Fryxellat the bottom of the valleys today with Kevin Lavigne, a teacher from Hanover (N.H.) High School. We met up with two researchers from the team he has joined for the season.
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A science team waits as building supplies are dropped at F6 Camp near Lake Fryxell. |
Kevin and his colleagues collected a set of soil samples from a dry stream bed that once flowed from one of the glaciers and into a lake that is now covered with snow. The full bed is more than 100 feet wide, but the only moisture that hits these days is in a small section.
Jeb Barrett, a postdoctoral fellow from Dartmouth College who’s working on the project, points to salt on the surface of the soil as a sign that the water flowed there this spring, probably in the middle of last month.
At this time of year, the team sees damp spots at points in the active stream bed, but hardly any other water. Even at the height of the runoff, the water’s flow is no more than a trickle, Jeb says. The lake it runs into is a pile of snow on top of ice.
The rest of the stream bed probably hasn’t had water flowing through it in hundreds, maybe even thousands, of years.
Today, Kevin, Jeb, and Andy Parsons dig samples, starting in the active stream bed and branching out through the dry sections. They fill plastic bags with about 1 kilogram of soil every 8 meters. When they analyze the soil back in the lab, they check whether nematodes, the microscopic worms that are at the top of the Dry Valleys’ food chain, are more numerous the closer they are to what passes for an active stream.
The team from Dartmouth and Colorado State University are part of a long-term project to study the ecological health of the Dry Valleys.
The researchers first came to Antarctica in 1989 to check whether nematodes live outside the active stream beds. Until then, scientists believed that life couldn’t be sustained in such an extreme desert.
To their surprise, the team found carbon in the soil, a sign that nematodes were living far away from the wet streams. Even so, 35 percent of the samples the researchers take show no signs of animal life.
In the past decade, the researchers have been asking questions about how the worms survive and how much moisture it takes for them to live, according to Diana Wall, the Colorado State professor heading the project. Now, they’re testing a theory that the worms are living off carbon left over from a lake that evaporated more than 12,000 years ago.
While the scientists see these valleys as a place for endless research, for me, they represent the contradictions of Antarctica. In a continent where the ice holds 90 percent of the world’s fresh water, I walk today in an area labeled the world’s driest place. In a continent that is uninhabitable for most species, soil ecologists are documenting that some worms survive some of the Earth’s harshest conditions.
The rest of the natural world seems so simple compared with here.
On Board the Polar Sea (Jan. 14)—Every year in January, a U.S. Coast Guard icebreaker arrives in Antarctica to swath through McMurdo Sound. We could see the mammoth ship chopping through the ice as we flew in 10 days ago.
The 400-foot-long vessel is designed with a rounded hull and a flat-bottom bow. With the full thrust of its six diesel engines, it slides on top of the ice it approaches and cracks it with the force of its weight.
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One hundred fifty visitors were treated to an afternoon on the Coast Guard icebreaker Polar Sea on Sunday, Jan. 14, as it worked to keep the sea channel in McMurdo Sound open. |
This year, however, the unusually large piles of snow on top of the ice made it especially hard for the cutter to shatter the ice. Landing on top of the snow was like “hitting a pillow with a hammer,” said Capt. Keith G. Johnson, the ship’s commanding officer.
The ship took four days to break through the 18 miles from the Ross Sea to the dock at McMurdo—a task that often takes only half a day, Johnson said.
The cutter docks in a cove between the McMurdo Research Station and Scott’s Discovery hut during its monthlong stay here. Every few days, it goes out toward the Ross Sea to break through the ice that forms around its channel.
Last week, a cruise ship of tourists pushed through the channel for a day to tour the research facility and the Discovery hut. Next week, a tanker is scheduled to arrive with 12 months of fuel for the airplanes, helicopters, and other vehicles that keep this operation running. The load is so big that it takes three days to pump the fuel into McMurdo’s storage tanks.
As McMurdo slows to its winter schedule in February, a supply ship will dock in the sound with the major delivery of canned food, durable goods, and everything else the research station will need for the next year. When the ship leaves, it will take with it scientific equipment, trash, recyclables, and other cargo headed back to the States.
While waiting to escort those ships to harbor, the Polar Sea will ferry scientists around the area for their research. In the coming weeks, it will take a group of geophysicists to one of the largest icebergs ever discovered. The original piece broke away into the Ross Sea last March. It was about the size of Connecticut. A University of Chicago research team will be tracking its progress as it breaks into pieces and circles the Antarctic waters. For now, the ship spends most its time maintaining the channel in the ice that it cut earlier this month.
The captain invited Allison Shelley and me to join him on a Sunday-afternoon cruise through the sound. We boarded with another 150 McMurdo residents given the chance to ride along on a “morale” cruise.
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Visitors enjoy gourmet coffee on the deck of the Coast Guard icebreaker Polar Sea as it pulls out of McMurdo on a four hour “morale cruise”. |
As the Polar Sea crashes through the chunks of ice that had drifted back into the channel, small groups of napping seals roll over to see the ship coming. Most squirm away as fast as they can. A few casually roll over and resume their naps. Those in retreat look as if they’d be better off if their flippers evolved into arms so they could get away faster.
One seal lying on a chunk of ice in the middle of the channel watches the bow of the ship headed toward him. At what seems like the last moment, he tips his nose off the tiny iceberg and slides into the water.
Every once in a while, a group of penguins is on the run in the distance. They have a choice between waddling or sliding. Most go the fastest way: They drop to their stomachs and push themselves with their wings.
As the Polar Sea turns around at the Ross Sea two hours into the ride, we see whales bobbing up and down in the water.
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Over one hundred McMurdo visitors, including Education Week’s own photo editor Allison Shelley, participate in the annual 4.5-mile Scott Hut Run in snowy conditions. |
With the channel having been open for more than a week, the ice is loose. The ride feels smooth on the deck. But once I climb to the bridge five stories above the hull, I feel the ship lurch forward as it hits big chunks. When the Polar Sea opened the channel last week, the crew says that each thrust into the ice felt like an earthquake.
On our way back to the dock, I notice that the channel already has a thin layer of ice over it. The big pieces are settling back into place. They look as if the only thing that can move them is 13,000 tons of ship pushed by engines with 18,000 horsepower.
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Tigger gives it his all at the finish line of the Scott Hut Run, placing 72nd overall. |
Earlier today, the McMurdo recreational office held its annual Scott’s Hut Race. The 4.5-mile race started outside the chapel as a church service was letting out at noon. The runners jogged to the hut, back through town, up a hill on the other side of town, and back to the hut-before returning to the finish line at the chapel.
The race is a big deal for everyone in the community here. The top male and female finishers in the South Pole station’s annual “Race Around the World” are flown in to represent their community.
My colleague Allison ran in the race, finishing in 40 minutes, 16 seconds. She was pleased with her time but was disappointed that a man dressed as the Winnie-the-Pooh character Tigger beat her by almost three minutes.
Photography made possible through a generous donation of digital equipment from the Eastman Kodak Company (Kodak.com).
